Despite more than a decade of efforts to prevent new infection by the human immunodeficiency virus (HIV) among injecting drug users (IDUs) through distribution of cleansing materials and/or sterile paraphernalia, IDUs in many parts of the world still engage in behavior that leads to infection by HIV. Efforts to distribute bleach, clean cottons and cookers, and clean water have tended to monitor their progress by collecting IDUs' self reports of risk reduction, but they offer little evidence of their impact based on observation of injection behaviors or detection of contamination. Needle exchange programs report reduced risk in increasingly convincing fashion, but not all places may be able to institute these programs. Some parts of the world, for political or economic reasons, cannot offer needle exchanges, and those places need some viable alternatives for preventing spread of HIV among IDUs. In order to develop focused, efficient interventions that can reduce risk in those places, the present application proposes to use detectable contamination of injection paraphernalia, determination of HIV status among clientele, and direct observation of self injection behavior as fundamental criteria for instituting and evaluating an intervention that distributes material for cleansing n/s (sodium hypochlorite solution) and replacing other paraphernalia (cottons, cookers, and standing water supplies). Project staff will engage proprietors of known risk locales to participate in the proposed intervention, providing cleansing/replacement materials on a "just in time" basis to at least ten risk locales, selecting half for training of personnel in cleansing technique. Contamination of paraphernalia in risk locales will be determined through polymerase chain reaction (PCR) methods for detecting HIV DNA and quantifying viral RNA. Observations of risk behavior coupled with PCR detection and quantification of HIV DNA and RNA will link specific behaviors to contamination, complemented by determinations of HIV status among clientele and laboratory experiments to replicate observed risk, and avoidance of risk through cleansing techniques. Determinations of RNA viral load would define level of risk in conjunction with the intervention's impact and experiment results.